Ticagrelor (TCG; 3-[7-[[(1R,2S)-2-(3,4-difluorophenyl)cyclopropyl]amino]-5-(propylthio)-3H-1,2,3-triazolo[4,5-d]pyrimidin-3-yl]-5-(2-hydroxyethoxy)-(1S,2S,3R,5S)-1,2-cyclopentanediol) having the following structural formula
shows pharmaceutical activity by functioning as a P2Y12 receptor antagonist and thus is indicated for the treatment or prevention of thrombotic events, for example stroke, heart attack, acute coronary syndrome or myocardial infection with ST elevation, other coronary artery diseases and arterial thrombosis as well as other disorders related to platelet aggregation (WO 2000/34283).
Ticagrelor (TCG) may exist in a number of different substantially crystalline forms (Polymorph I, Polymorph II, Polymorph III and Polymorph IV) as described in WO2001/092262.
In addition, WO2011/067571 discloses co-crystals of ticagrelor and a co-former molecule selected from glycolic acid, salicylic acid, decanoic acid, gentisic, acid, glutaric acid, vanillic acid, succinic acid, malonic acid and maltol.
International applications WO2000/034283 and WO2010/030224 describe a process of purification of ticagrelor by crystallization.